outlook 2007

I have 3 clerks who use eachothers computers at various times when they need
to fill in for eachother. They need access to their Outlook content, mail,
calendars, contacts, etc. We have an exchange server. Currently, a "copy"
was created of the calendar, contacts, etc. However, that "copy" does not
show up when they sign on to one of the other computers, the default info
shows.
Do you have any ideas?

Thanks!
Sheila